Plastic surgery, dermatology and otolaryngology involve medical procedures for improving and/or restoring the form and function of a body. Over the years, medical practitioners have developed a number of techniques and technologies to facilitate their art. From the earliest skin flap done by Tagliacozzi, the movement of tissue has benefited the form, appearance and function of patients. This tissue movement includes cosmetic and reconstructive procedures, such as breast augmentation, breast reconstruction, abdominoplasty, liposuction, nasal surgery, eyelid surgery and sub-dermal injections to restore tissue and volume.
Popular sub-dermal injections include injections of fillers, Botulinum Toxin (“Botox”), fat transfer and subcutaneous threads. Injections of sub-dermal substances are minimally invasive procedures to add substances, remove substances, stimulate tissues, lift tissues or tighten tissues to alter the contours of the face and body. Substances are also injected to dissolve fat and fillers. Common areas to inject sub-dermal substances are in the face, neck, hands, breasts and buttocks resulting in a contour change to create a restored, more youthful appearance. The types of injectable substances available include, but are not limited to, deoxycholic (bile) acid, hyaluronic acids, collagen-stimulating tumescent and autologous fillers (fat, platelet rich plasma), Botox, lidocaine, saline, hyaluronic acid fillers, synthetic wrinkle fillers (e.g., calcium hydroxyapatite, poly-1-lactic acid, poly glycolic acid), collagen wrinkle fillers, poly methyl methacrylate with bovine collagen, autologous wrinkle fillers, absorbable threads, non-absorbable threads and tumescent anesthesia solutions (collectively “medications” or “sub-dermal substances”).
The most commonly used sub-dermal substances are hyaluronic acid fillers, collagen-stimulating fillers and Botox. Hyaluronic fillers are cross-linked hyaluronic acids typically used to naturally augment the lips and fill the areas of the face which lose volume with age, such as the temples, mid-cheek break, tear through, nasolabial fold and marionette lines. They are equally useful in men and women, although currently used more commonly in men. Hyaluronic acids are volumizing agents which typically last for six months to two years.
Collagen-stimulating fillers, such as sculptra poly-1-lactic acid, radiesse and calcium hydroxyapatite, are typically injected throughout the whole face to provide more structural volumizing. They typically last at least 18 months.
When injected, Botox blocks the nerve signals that cause muscles to contract. This effect relaxes and smoothes the look of lines and wrinkles caused by repetitive movements on the face—most commonly, between the brows (i.e., the frown), crows-feet around the eyes, and horizontal forehead creases. Botox is also used cosmetically to balance facial symmetry and relax tight neck bands, as well as medically to reduce perspiration, treat migraine headaches and treat muscle spasticity. Fat grafting is a procedure that involves the transfer of fat from areas where a patient has excess fat, such as the flanks and thighs, into areas that would benefit from added volume, stem cells or platelet rich plasma [PRP], such as the face, hands, breasts or buttocks.
Sub-dermal injections are typically performed using a needle attached to or coupled with a syringe. While a syringe with a sharp tipped needle is useful for penetrating a patient's skin, that same sharp tipped needle can cause significant bruising, vessel laceration, soft tissue necrosis and even blindness when the sharp needle transgresses vascular structures. Transgression of vascular structures is virtually unavoidable using a needle alone. For this reason, many medical practitioners prefer using a blunt tipped instrument, such as a blunt-tipped cannula, to administer sub-dermal substances to a patient. Nonetheless, since its tip is blunt, the blunt-tipped cannula is unable to readily penetrate the surface of the skin.
It is becoming increasingly popular for plastic surgeons and other medical practitioners to use a combination of a sharp-tipped needle (including a lancet, scalpel, trough or trocar) and a blunt-tipped cannula for their sub-dermal injections in a two-step process. First, the medical practitioner uses the sharp-tipped needle to puncture a hole in the patient's skin. The sharp-tipped needle is then withdrawn from the hole and the cannula is inserted into the hole so the substance can be delivered or withdrawn from within the subcutaneous space.
While this two-step process is simple in concept, it is not simple in application. For example, after the sharp-tipped needle is withdrawn from the patient's skin, it is often difficult for the medical practitioner to find the hole created by the sharp-tipped needle. He or she must also find a place to put the needle down. It can be awkward, time-consuming and embarrassing for the medical practitioner to hunt for the needle hole. Despite creating better aesthetic results for the patient with less risk, the current two-step needle-cannula process is more difficult for the medical practitioner to manage. As a result, many medical practitioners are reluctant to adopt the current two-step needle-cannula process and, instead, simply use a hypodermic needle attached to a syringe to administer sub-dermal substances. Although blunt-tipped cannula use for the administration of sub-dermal substances should become the standard of care for these procedures, the current technical and practical difficulties in using them in two un-integrated steps serves as an impediment to the adoption of the safer cannula technique.
What is needed is a way for medical practitioners to make injections quickly, easily and accurately using both a needle for puncturing the skin and a blunt-tipped cannula connected to a syringe for injecting the sub-dermal substances.